Gas and oil burner



Jan. 30, 1945.

w. s. PATTERSON GAS AND OIL BURNER Filed March 50, 1945 INVENTOR flkradiJlfersan 247 TURN/f Y Patented Jan. 30, 1945 Gas AND on. BURNER Ward S.Patterson, Chappaqua, N. Y., assi:nor to Combustion Engineering Company,Inc., New

York, -N. Y.

Application March 30, 1943, Serial No. 481,081

This invention relates to fuel burners tively. I

When blast furnace gas is burned as fuel to release heat in a furnace,the burner has fuel and air passages with cross-sectional areasproportioned for the correct ratio of air to fuel and certain suitableair Y velocities. When oil is .burned in the same burner toreleaseapproximately the same amount of heat in the furnace, the airpassages of the burner being designed for the blast furnace gas are theninsufllcient in area to maintain suitable air velocities. This isaccounted forv by the different air-quantities required bythe two fuels,oil requiring about thirty percent more than blast furnace gas.Therefore, when using oil as-fuel, the air velocities through the,burner passages would be about thirty per cent higher than when usingblast furnace gas. Such velocities are undesirably high and require morepower to move the air.

It i an object of this invention to provide an improved burner in whichthe above dimculties are overcome.

In the accompanying drawing:

Figure 1 is a longitudinal section through a burner embodying theinvention; and

Figure 2 is a transverse section through the air valve and ports takenon the line 2-2 of Figure 1.

In the drawing, the burner designated as a whole by the numeral III hasa cylindrical tube Ii disposed horizontally and itstip l2 projects intoan aperture H in the furnace wall It. The burner 10 has a voluteentrance section l5 through which blast furnace gas is suppliedtangentially to the burner nozzle through a. pipe supply It.

Secondary air is delivered to theltip of burner In from a windbox"through which the burner and slot connection .to an operating ring 25.As

ring 25 is rotated clockwise the dampers 22 separate with respect to oneanother and open to permit secondary air to flow through chamber 20around bumer I hand when the ring isrotated counterclockwise the dampersclose and reduce the air flow.

lClaiin, (cuss-11).

nd par-4., ticularly to burners for using two fuels alterna- I 'It habeen found that whenair enters the windbox I! in one general direction,as downward in Fig. 1, a major part of the secondary air supply entersthe annular chamber around burner through the upper part of "port 2|.

Little air enters around other parts of the,

burner, as at the lower part thereof. zThis'inequality of air supplythrough port 2| around the burner prevails in the travel of the airtoward the furnace-through the annular chamber "and results in an unevendistribution" of the secondary air discharging into the furnace aroundthe burner tip II. This in turn causes .40 P oj ts- Th nozzle section ofburner Ill is, en-

furnace and inefllcient combustion. f

A baflle 26 having a conical outer surface 21 extends inwardly from thecasing 28 of windbox,

I1 across the circumferential port 2| in'burner casing I8. The inneredge of bame 28.1s substantially in alinement with but spaced from thefurnace -side edge of port 2| to provide a vertical annular opening 20through which the windbox is in communication with the enclosed spacearound-port2L- 1 I 'Bame 25 prevents air from. flowing directly intoport 2| from thewindbox l1 and causes it to flow through annular opening30 around the entire circumference of battle 26 toward port 2| in adirection substantially parallel to the axis of the burner. Thence theair turns 90. into the a port 2| and again 90 intochamber 20 to passtoward the burner tip l2. By blocking the direct entry of the airintoiJort-ZI from any direction by means of banle 26 the velocity of theair from that direction is diminished and is no longer effective tocause an excess flow of air from that direction into the burner. Thus,all ofthe air is then forced to enter port 2| through opening 30 atright angles to its direction of flow in windbox, I! and then caused tomake an abrupt turn into port 2| therebysubstantially equalizingresistance to air flow into the burner.

Adjacent its juncture with its conical nozzle tip |2 the fuel nozzle isprovided with a plurality of apertures Olports ll Surrounding and 7covering the ports 3| is a cylindrical sleeve 12 provided with a dance83. Movement of sleeve 32 to cover or uncover ports 8| is accomplishedbyv rods 34 attached thereto.

When blast furnace gas is tobe burned-it flows from pipe l6 throughburner tube ll into the furnace'while the air for combustion flowsseparately from. windbox I! through port III and annular conduit 20around the nozzle tip l2 into the furnace to therein mix with and burnthe thirty percent more than when burning blast furnace gas andconsequently the air velocities through port 2| and conduit 20- are\msuitably high. This would result in a high windbox ir e -w surerequirement and a poor control of thee flame shape. v p g To overcomethis ditflculty andto permit a maximum heat release with a; combinationburner, the ports 3| are uncovered lag moving sleeve longitudinally ofthe fuel tube.

sleeve 32, acting as awalve, allows air from port 2| to flow into-theburner tube i! and thence to the furnace. 3 v

when the sleeve 32 is i 'itssrightfhand position, port 2! is extended orwidened asthe flange 33 defining one side thereof recedes therebyproportionately increasing the area of the air opening from windbox l'linto the furnace via conduit 20, ports 3! andthe burner tube II. Inorder to maintain damper'control of the increased amount of air, thedampers 22 are made L-shaped to lie alongside flange '33 and wide enoughto extend .over the extension of port 28 produced by retracting flange"33.

' air supply port in the wall thereof opposite the The burner may beused with other fuels blast-furnace gas and oil where such fuels requiresubstantially diflerent quantities of air for combustion.

5 What! claim is:

In a dual purpose iuel burner; a. nozzle tube arranged to be supplied atone end with gaseous fuel and to discharge it into a iurnace at itsopposite end and provided with a plurality of 19 air ports in the wallthereof near its discharge end; a casing surrounding said nozzle tubeand forming therewith an annular chamber through which air may flowaround said nozzle to the" discharge end thereof a windbox contiguous tosaid casing, said casing being provided with an ports'insaid nozzle tubefor admitting air to said chamber from said windbox; a secondary fuelnozzle co-axially positioned within said noz- 20 zle tube; a slide valvemounted on said nozzle tube; a flange on said slide valve extendingacross said annular chamber to the casing that forms the. outer wall ofsaid chamber and so located with respect to the edge 01' the port in 25said casing nearest the nozzle ti as'to narrow the width-of said port insaid casing when said slide valve is positioned to close the ports insaidnozzle tube; and means conneoted to said slide valve for moving itin a direction away from the I 30 tip'of said'nozzle to uncover saidports and for' positioningsaid flange further away from the edge oi theport in said casing to increase the" width thereof.

36 WARD s. PATTERSON.

